Fuel pump for motor vehicles



Sept. 5, 1933. H. HUEBER ET AL FUEL PUMP FOR MOTOR VEHICLES Filed Feb.26, 1950 2 Sheets-Sheet l Henry Haebez- 6?.

Erwin azyoribzz,

Sept, 5, 1933. H. HUEBER ET AL I 1,926,005

FUEL PUMP FOR MOTOR VEHICLES Filed Feb. 26, 1930 2 Sheets-$heet 2 Ezwima Harazv Patented Sept, 5, 219333 STATE iii @FHQE FUEL PUMP F018, M@'H%VEIHUIGILIES Application February 26, 1936. Serial No. Q3158? lidClaims.

This invention relates to a fuel feed system for internal combustionengines and is primarily designed for furnishing the internal combustionengine of motor vehicles with a constant supply of liquid fuel.

Considerable attention has been given by automotive engineers to theproblem of supplying the engine with a sufficient quantity of the liquidfuel under all operating conditions. In the prevailing arrangement,found in the modern motor vehicle, the fuel'supply tank is disposed atthe rear of the motor vehicle and the liquid fuel is transferredtherefrom to the carburetor through the intermediary of power operateddevices among which the vacuum tank and the engine operated pump are thebest known.

In the fuel feed system utilizing the vacuum tank, the gasoline islifted from the supply tank to the vacuum tank by a negative pressure orso-called suction as found in the intake manifold of the internalcombustion engine. This source of suction produces a variable degree ofsuction, from a degree sufficient for the normal operation of the vacuumtank mechanism as when the engine is idling or its throttle is more orless closed, to a degree insufficient to lift the gasoline to the tankas when the engine is laboring or being accelerated and the throttle ismore or less fully opened. Therefore, with the engine accelerating andoperating at a high speed, as during fast traveling, the liquid fuel isnot supplied to the carburetor with sufficient volume or constant flowto meet the demand, with a resultant inefilciency in the behavior of theengine.

In the positive pressure type of fuel lift for transferring the liquidfuelfrom the supply tank to the carburetor, there is interposed in thefuel line a mechanically driven pump in which the impeller, Whether itbe of the piston type or diaphragm type, is operated from the cam shaftor through the intermediary of other mechanical movements from, and inaccordance with the speed of, the engine. Consequently, there isconsiderable wear and tear on the pump mechanism by reason of theaccelerated speed of operation and movement of the cooperating parts,with no particular way of gauging the flow and therefore a consequentialover or under supply of the liquid fuel occurs. In the case of an oversupply of the fuel a by-pass or return passage must be provided to avoidrupturing the fuel line or otherwise disrupting the system.

It has also been suggested to utilize a diaphragm pump in which thediaphragm is operated by pulsations, but the action has failed to (Cl.1&93-152) perform and has been 'such as to subject the diaphragm tostrains and stresses which materially shortened its period ofusefulness.

The present invention has for its objects to provide a fuel system whichwill be more efiicient and longer lived in the actual service oftransferring the motor fuel from the supply tank to the carburetor; toprovide a controlled fuel feeding from a lower lever to a higher level,governed in accordance with the demand made by the engine withoutexceeding the requirements; and to provide a fuel transfer pump in whichthe piston member is in the form of a substantially non-resilientdiaphragm, the diaphragm preferably having a fabric or fiber body. 76The fuel feeding system, as a system, and which is hereinafter referredto, forms the subject matter of our co-pending divisional applicationfiled December 27, 1932, Serial No. 649,052.

The invention further resides in the provision of an improved fuelfeeding pump of the diaphragm type wherein the life and usefulness ofthe diaphragm is materially increased and reflex bending or bucklingmovements of such element are avoided; to provide a diaphragm pumpembodying valved atmospheric and suction ports in which the valves arecontrolled and actuated by a spring snap action to insure and effect adefinite and positive seating and unseating of the valves in properorder and relationship whereby the dry side of the diaphragm issubjected first to a negative motivating pressure and then anatmospheric relieving pressurefand to provide a diaphragm pump in whichthe diaphragm is subjected to a negative lifting pressure for taking ina quantity of the liquid fuel, and then subjected to a yielding urge orpressure for expelling the quantity of liquid fuel in accordance withthe demand.

The invention still further resides in the provision of a diaphragm liftin which the diaphragm is of fabric or cloth and is maintained belliedor flexed to one side against reflexing during operation.

In the drawings: 100

Fig. l is a fragmentary perspective view showing the improved fuelfeeding system. incorporated in the motor vehicle power plant, theauxiliary suction producing mechanism being de 105 picted in section. I

Fig. 2 is a vertical sectional View through the fuel lift mechanism inthe act of intaking liquid fuel.

Fig. 3 is a vertical sectional view through the 110 fuel lift taken on avertical plane substantially at right angles to the plane of section ofFig. 2.

Fig. 4 is a detailed perspective view of the spring holding member.

Fig. 5 is a fragmentary plan view of that section of the lift casing atthe wet side of the diaphragm.

Fig. 6 is a diagrammatic showing of the snap action.

Fig. 7 is a sectional view through the suction Referring more in detailto the accompanying drawings, the numeral 1 designates the intakemanifold of the motor vehicle engine 2 having the usual carburetor 3 towhich leads the fuel line 4, 4 from the supply tank 4" (Fig. 3) locatedat a level lower than the carburetor and which is usually disposed atthe rear of the motor vehicle.

Interposed in the fuel line is the power lift which, as illustrated inFigs. 2, 3 and 4, comprises a casing having an upper section 5 and alower section 6 to which latter may be secured a sediment trap '7, as bymeans of a removable ball 8 and a clamping adjustment 9. Interposedbetween the upper and lower sections 5 and 6 is a diaphragm 10,preferably of a treated fabric and dividing the interior of the casing5, 6 into an upper dry chamber 11 and a lower wet chamber 12. Thenumeral 13 designates the inlet passage for the liquid fuel having aport 14 designed for being closed by a valve 15 against retrograde flowof the liquid fuel.

For trapping any dirt lifted from the supply tank with the gasoline ormotor vehicle, the intake passage 13 first opens downwardly into hesediment trap or chamber 7, as through an annular groove or channel 13'.A screen or strainer 16 is provided in the sediment trap at the outletside thereof, herein shown held in position by being clamped against theunderside of the casing 6. The liquid fuel passes from the sediment trapupwardly through the strainer 16 into the annular chamber 17 and thencethrough the inlet port 14 into the fuel chamber 12, at the underside orwet side of the diaphragm 10, unseating the valve 15 in its upwardpassage. A spider 18 may be provided for preventing total displacementof the valve. The outlet for the liquid fuel chamber 12 is designated bythe numeral 19 and is closed by an inwardly closing valve 20,communication being had with the outlet port 19 through a horizontalpassage 21 and a vertical passage 22 opening upwardly into the chamber12, this indirect passage permitting the use of a gravity seated outletvalve 20 which may also be restricted in its movement from its seat bythe extension 18' of the spider 18.

The upper chamber 11 has an inlet, atmospheric port 23 closed atintervals by a valve 24, and an outlet suction port 25 connected to thesource of suction and closed at intervals by a valve 26. The two valvesare alternately seated and alternately unseated by a snap action whichfunctions at the opposite limits of movement of the diaphragm. As thediaphragm reaches its lower limit, on the liquid expelling stroke, thevalve 24 is seated and the valve 26 unseated whereby suction willmaintain in the chamber 11 to urge the diaphragm upwardly for drawing inanother quantity of gasoline, the valves remaining in suchpositionsuntil the diaphragm about reaches its upper limit of movement when thevalve 26 will close and the valve 24 open, breaking the liftinginfluence of the suction and permit the liquid expelling movement of thediaphragm.

This liquid expelling movement is provided by a constantly urging forceor pressure, of a yieldable character whereby the liquid fuel issupplied only as the carburetor demands the same. In the illustratedembodiment this movement is imparted by a spring-27 preferably connectedto the underside of the diaphragm and anchored at a suitable point suchas by means of a pin 28 in the bottom of the well 29. A removable cap 30may be provided over the bottom of the well to facilitate the anchoringof the lower end of the spring in practice; This spring is of suflicientstrength to create a downward movement of the diaphragm when the upperchamber 11 is in communication with the atmosphere whereby the liquidfuel in the chamber 12 will be expelled through the outlet 19 and pipe 4into the carburetor 3. When the chamber 11 is in communication with thesource of suction the urge of the negative pressure on the upper side ofthe diaphragm will be sufficient to overcome the downward urge of thespring 27.

To insure a positive and quick change over from the suction supply tothe atmosphere there is embodied in the lift a spring snap action. Thissnap action preferably consists of a valve actuator or lever 31 pivotedat 32 adjacent one end to rock in a vertical plane. The lever isprovided with a valve actuating stem 33, designed to unseat the valve24, and a second valve actuating stem 34 designed to actuate the valve26. For simplicity, the stems have openings through which the end of thelever is threaded, or loosely passed.

The diaphragm may have central disks 10' to facilitate the attachment ofthe spring 27 and constitute a means for mounting the standard orupright plate 36. This plate has outturned ears 40 between which acoiled spring 35 is suspended. The intermediate portion of this springmay flex up and down from a normal position and is adapted to beconnected to the lever 31, as by means of a saddle 37 which is suspendedfrom thelever and encloses the spring 35. The

plate also has upper and lower lugs or shoulders 38 above and below thespring and adjacent its points of suspension. The spring is designed toalternately bear on these lugs as it flexes up and down to avoidsubstantial pivoting of the spring about the ears 40. Fuel intakingmovement of the diaphragm will flex the spring downwardly, as indicatedapproximately by the dotted showing 35 in Fig. 6, thereby placing thespring under sufficient lateral tension to bring the valve 26 to itsseat for closing communication with the source of suction and to quicklyand simultaneously unseat the valve 24 whereby the negative pressure inthe chamber 11 will rise to atmospheric pressure and the spring 27,having its counteracting force disrupted, will urge and pull thediaphragm downwardly for expelling the liquid fuel. As the diaphragmcontinues its liquid expelling movement the spring 35 returns to itsnormal position (Fig. 3) and moves beyond or to the opposite sidethereof whereby the spring is again flexed laterally but upwardly,substantially as indicated by the full lined showing in Fig. 6, and whenthe spring potential has built up sufficiently to overcome the pressureacting to hold the valve 26 seated the spring will act quickly to unseatthe valve 26 and seat the valve 24. again restoring communicationbetween the chamber 11 and the source of suction to the exclusion of theexterior atmosphere whereupon upward travel of the dia-= phragm willagain begin.

After the spring 35 has been placed under sufficient tension to eifect aquick shifting of the valve, it is desired to provide a positiveconnection between the lever 31 and the diaphragm which in the presentshowing is obtained through the saddle 37 coming alternately intocontact indirectly with spaced shoulders 39 and directly with thediaphragm assembly. The shoulders 39 project from the upright plate 36at opposite sides of the saddle and above the spring 35, being disposedclose to the saddle so that the intermediate spring portions willpractically constitute rigid abutments or connections therebetween whenthe shoulders are engaged with the spring. Thus, when the spring hasbeen flexed to the position 35' (Fig. 6) the saddle 3'? will contactwith'the diaphragm plate 10', or other fixed part thereon, to provide adirect thrust connection between the diaphragm and the lever 31 topositively unseat the valve 24 whereupon the stored up energy in thespring 35 will act unrestrictedly in seating the valve 26,.and viceversa, when the spring has been flexed to the full lined position inFig. 6

the saddle will indirectly engage the shoulders 39 (through the portionsof the spring 35 between the saddle and the shoulders 39) and establishpositive connection between the lever 31 and the diaphragm to positivelyunseat the valve 26 whereupon the stored up energy of the spring 35 willexpend itself in bringing the valve 24 to its seat.

The suction port 25 is connected to the intake manifold through theconduit 42, 42', and since it is well known that the manifold suctionfluctuates considerablyranging between a very high or excessive degreeto an almost negligible degree-there is also provided an auxiliarydevice which is positively driven for creating a supplementing supply ofsuction which together with the manifold suction will provide asubstantially constant supply for the operation of the lift regardlessof the throttle position in the manifold.

The auxiliary suction producer preferably comprises a suction pumpdriven by the automobile engine. This pump, as shown, consists of acasing 43 and a piston 44 operable therein and having a piston rod 45extending upwardly through the head of the casing 43 where it issupported in an elevated position by a spring 46 the latter beingcompressed between a fixed part of the head and a collar 47 carried bythe piston rod. Overlying the upper end of the piston rod is a powerdriven actuator 48 extending within the crank case 49 of the engine forbeing operated by a cam on the cam shaft, or otherwise. A housing 50encloses the actuator 48 and serves to support the pump casing from thecrank case. The pipe 42 leads to the inlet port 51 while the pipe 42'communicates with the outlet port 52 of the pump, these two ports beingrespectively provided with check valves 53 and 54 for directing the flowof fluid through the piston chamber of the pump from the lift to themanifold. The spring 46 tends to establish the connection between theactuator and the piston rod 45 but its force is overcome by the manifoldsuction when the latter is sufficient of itself to operate the lift, oris in excess thereof. When the manifold suction is of such a degree thepiston 44 will be drawn downwardly thereby and consequently withdraw thepiston rod 45 more or less from the operative path of the actuator. Anexcess degree of manifold suction will completely withdraw the pistonfrom any operating contact with or by the actuator. 'I he pistontherefore constitutes a suction responsive member for rendering theconnection active or inactive.

To maintain a substantially uniform degree of negative pressure there isalso provided means for tempering or throttling the influence of theexcessive manifold suction on the lift, which means is preferably underthe control of the influenced piston 44 and in the present showingcomprises a valve 55 carried by the piston 44 and movable thereby towardand from the valve seat 56 about the outlet port 52. An imperfectseating of the valve 55 is provided for, such as by means of a bleedpassage 57 so as to avoid complete interruption between the manifold andthe lift. Obviously, as the manifold suction increases to an excessivedegree the valve 55 will be moved closer to its seat 56 and vary thesize of the port 52 with its increasing resultant restriction upon theinfluence on the lift.

In starting the engine with the valve 24 seated and the valve 26opened,.the manifold suction will create a lifting action on the upperor dry side of the diaphragm whereby the liquid from the fuel tank 4" isdrawn into the chamber 12 past the unseated inlet valve 15, the outletvalve 20 being held seated by such lifting action of the diaphragm. Uponcompletion of the lifting stroke of the diaphragm, as defined by thesnap action imparted by spring 35, the communication with the source ofsuction is interrupted by the seating of the valve 26 and atmosphericcom munication established by the unseating of the valve 24, breakingthe vacuous condition in chamber 11 and permitting the motivatingelement 27 to come into play for exerting a downward pres-' sure on thediaphragm which causes the inlet valve 15 to seat and the outlet valve20 to unseat with a consequent expelling of the liquid fuel from thechamber 12 on into the carburetor. This expelling action is elastic oryieldable thereby providing a constant propelling influence on the fuelin the chamber 12 so that the motor fuel will be forced into thecarburetor as the latter requires the same in meeting the demands of theengine.

As the engine throttle is opened more and more, the available manifoldsuction decreases whereupon the spring 42 will overcome the manifoldsuction influence and bring the piston rod 45 into the operative path ofthe actuator 48 so that a mechanical production of negative pressurewill start up, since the action of the plunger 44 is to intake the airfrom the lift chamber 11, through pipe 42, past inlet valve 53 and intothe piston chamber in casing 43, and expel it therefrom through outlet42, past outlet valve 54 and, by means of pipe 42', deliver it to themanifold 1. As soon as the manifold suction' again reaches its normal orexcessive degree of suction the auxiliary, mechanically driven suctionproducer is rendered inoperative while the lift continues its rhythmicoperation (varied only by a change in the demand) ,as though theauxiliary suction producer was not present, except as to the throttlingaction which it brings into play when the manifold suction becomesexcessive.

The improved fuel feeding system will therefore maintain a constantsupply of fuel for all engine requirements and demands without an oversupply and without having a mechanically driven pump or lift which isunder constant driving pressure or connection with the engine.

Furthermore, the improved fuel feeding system maintains a constantsupply of negative pressure furnished largely by the manifold suctionand supplemented by the auxiliary pump only as the manifold suction mayrequire a boosting or augmenting component. The air is practicallyundergoing a constant change in the pressure chamber 11, taking in afresh supply of air during the ensmallment of the fuel chamber 12 andpassing it on into the intake manifold on the enlargement of said fuelchamber.

The life of the diaphragm is materially lengthened and may beconstructed from thin stock since in its action it is not subjected toviolent pressures and stresses, nor is it reflexed or turned over uponitself, the flexure being always to the same side of the diaphragm. Thepressures on the diaphragm at both sides are of a yielding nature, thedry side being subject to a fluid pressure preferably not aboveatmospheric, while the pressures or forces applied to the wet side andconsisting of the spring 27 and the atmosphere forcing the fuel into thechamber 12, do not exceed atmospheric. I

Even a single ply fabric diaphragm will stand up in service materiallylonger than the metal diaphragm, or the multiply fabric diaphragm whenmechanically driven, since there is no element in the improved liftwhich directly or indirectly reflexes the diaphragm or causes it to bendor turn upon itself. The central disks 10' give to the fabric arigidness suflicient to support or attach the spring 27 and the snapaction, leaving the surrounding diaphragm portion free to flex but whichflexes only toward the dry side.

What is claimed is: Q

1. A fuel lift comprising a casing having a fuel chamber and a pressurechamber divided by a flexible non-resilient diaphragm supported at itsmargin and having its central portion free to flex, said fuel chamberhaving valved inlet and outlet ports and said pressure chamber havingvalved inlet and outlet ports one of which latter ports is connectibleto a source of operating pressure, a spring urging the diaphragm andconstituting the sole source of power therefor in one direction ofmovement to ensmall one of said chambers, and mechanism for operativelycontrolling the admission of operating pressure to the pressure chamberfor moving the diaphragm against the tensioning of said spring toenlarge said specified chamber.

2. A fuel lift comprising a casing having a fuel chamber and a pressurechamber, a non-resilient flexible diaphragm means dividingthe twochambers and acting to ensmall and enlarge the fuel chamber, a springconnected to the central portion of the diaphragm and constantly urgingthe sameto ensmall the fuel chamber whereby the outer portion of thediaphragm is flexed away from said fuel chamber, and means adapted foroperatlvely connecting the pressure chamber first -to a source ofsuction and then to the atmosforced against flexing and to define arigid effective displacing area, means exerting a constant pressure onthe reinforced central portion of the diaphragm in one direction ofmovement of the diaphragm, said pressure chamber ports constituting anoperating pressure port and an atmospheric pressure port, valvescontrolling said ports, means connecting said pressure chamber valvesfor simultaneous movement to effect a seating of one valve and aconcurrent unseating of the companion valve, and vice versa, resilientmeans connecting the valve connecting means to the diaphragm for beingtensioned during both in and out movements of the diaphragm foreffecting a continued operation of said valve connecting means when suchmovement has been initiated.

4. A fuel lift comprising a casing having a fuel chamber and a pressurechamber, a fabric diaphragm dividing the chambers and operating toensmall and enlarge the same, means exerting pressure on the diaphragmconstantly in one direction and constituting the sole mechanical forcefor moving the diaphragm in such direction, said pressure chamber havingan operating pressure port and an atmospheric pressure port, valvescontrolling said ports, and a valve snap action interposed between bothpressure chamber valves and the diaphragm for effecting a seating of onevalve and a concurrent unseating of the companion valve, and vice versa,during in and out movement of the diaphragm.

5. A fuel lift comprising a casing, a fabric diaphragm dividing the sameinto a dry chamber and a wet chamber, each chamber having valved inletand outlet ports, the central portion of the diaphragm being rigid, anda snap action carried in part by said central rigid portion ofthediaphragm and operable by and during movement of the diaphragm forseating the inlet valve and opening the outlet valve of the dry chamber,and vice versa.

6. A fuel lift comprising a casing, a flexible but non-resilient fabricdiaphragm secured about its edges therein and dividing the casinginterior into a dry chamber and a wet chamber,

each chamber having inlet and outlet ports, the

outlet port of the dry chamber being connectible to a source of suctionand the inlet port to the atmosphere, snap-acting valve mechanismoperable by the diaphragm for intermittently opening and closing theoutlet port of the dry chamber whereby the suction influence on thefabric diaphragm s completely relieved at intervals, and resilient meansacting on the diaphragm for moving it to ensmall the wet chamber whenthe outlet port of the dry chamber is closed.

7. A fuel lift comprising a casing, a non-resilient diaphragm dividingthe easing into a fuel chamber and a suction chamber, a spring anchoredat one end in the fuel chamber and connected centrally of and to thediaphragm for exerting a pull on the latter to expel fuel from said fuelchamber, and means controlled by the diaphragm for alternately openingthe pressure chamber first to a source of suction and then to theatmosphere, the suction when admitted to the pressure chamber acting tomove the diaphragm against the action of said spring for intaking fuelinto the fuel chamber, the diaphragm between the point of securement ofthe spring thereto and its marginal mounting in the casing beingconstantly bulged toward the pressure chamber side to avoid back andforth buckling of the diaphragm.

8. A fuel lift having a fuel chamber with valved inlet and outlet ports,a fabric diaphragm arranged in the chamber and operable to enlarge andensmall the chamber for the intaking and expelling of fuel, a suctionchamber divided from the fuel chamber by said diaphragm and having asuction port and an atmospheric port, valves for controlling saidsuction chamber ports, means independent of the diaphragm for impartinga fuel expelling movement to the diaphragm and constituting the solemeans for moving the diaphragm during such movement, and snap actingmeans operable by and during movement of the diaphragm to open thesuction port and simultaneously close the atmospheric port at the closeof such diaphragm movement to thereby connect the suction chamber to asource of suction for effecting a fuel intaking movement of thediaphragm, said snap acting means acting at the end of such intakingmovement and independently of further diaphragm movement to close thesuction port and to simultaneously open the atmospheric port to permitsaid diaphragm moving means to again actuate the diaphragm for expellingfuel.

9.1% fuel lift having a fuel chamber with valved inlet and outlet ports,a non-resilient diaphragm arranged in the chamber and operable toalternately enlarge and ensmall the chamber, a suction chamber dividedfrom the fuel chamber by said diaphragm and having a suction port and anatmospheric port, valves for controlling said suction chamber ports,means for constantly urging a fuel expelling movement of the diaphragm,valve actuating means movable in one direction for simultaneouslyclosing the suction port and opening the atmospheric port of saidsuction chamber and movable in a reverse direction for reversing thepositionst of said suction chamber valves, and means connecting saidvalve actuating means to said diaphragm for operation thereby andembodying a spring snap-over action for effecting a quick change-over inthe positions of the suction cham,

ber valves.

10. A fuel lift having a fuel chamber with valve inlet and outlet ports,a diaphragm arranged in the chamber and operable to enlarge and ensmallthe chamber for intal ing and ex pelling fuel, a suction chamber dividedfrom the fuel chamber by said diaphragm and having a suction port and anatmospheric port, valves for controlling said suction chamber ports,means for imparting a fuel expelling movement of the diaphragm, valveactuating means movable in one direction for simultaneously closing thesuction port and opening the atmospheric port of said suction chamberand movable in a reverse direction for simultaneously opening thesuction port and closing the atmospheric port, said valveactuating meansembodying a support having spaced ears, a spring suspended by andbetween said ears, and a connecting member, said support, spring andconnecting member acting upon up and down movement of the diaphragm tooperatively dispose the suction chamber valves.

11. A fuel lift having a fuel chamber with valve inlet and outlet ports,a diaphragm arranged in the chamber and operable to enlarge and ensmallthe chamber for intaking and expelling fuel, a suction chamber dividedfrom the fuel chamber by said diaphragnrand having a suction port and anatmospheric port, valves for controlling said suction chamber ports, anactuator for the valves, a member in the suction chamber having spacedarms, a spring suspended by and between said arms, a connecting memberengaged with the spring and adapted to tension the spring, said springacting upon up and down movement of the diaphragm to operatively disposethe suction chamber valves, and means for establishing a positiveconnection between the diaphragm and actuator subsequent to thetensioning of the spring by said connecting member whereby movement ofthe diaphragm in one direction will simultaneously close the suctionport and open the atmospheric port of said suction chamber and uponmovement in a reverse direction simultaneously open the suction port andclose the atmospheric port.

12. A fluid pump having a pump chamber with inlet and outlet passagemeans, a flexible non-resilient diaphragm forming a wall of the pumpchamber and operating on its intaking stroke to enlarge the chamber andon its expelling stroke to ensmall the chamber; means plac ing aconstant urge on the diaphragmin its fluid expelling direction ofmovement and solely acting to move yieldingly the diaphragm on itsexpelling stroke, and means intermittently acting to move the diaphragmon its intaking stroke and against the constant urge of said firstdiaphragm moving means, said intermittently acting means when operativeovercoming the first diaphragm moving means.

13. A fuel lift comprising a casing, a fabric diaphragm dividing thesame into a dry chamber and a Wet chamber, each chamber having valvedinlet and outlet ports, means for intermittently applying suction to thedry chamber for urging the diaphragm in one direction of movement, andmeans separate and distinct from the'diaphragm and constituting the solemeans for creating a constant urge on the diaphragm in the oppositedirection for moving the diaphragm in the absence of the suctionapplication, said diaphragm being flexed toward the dry chamberthroughout its movements in opposite directions.

14. A fuel feed device comprising a casing, a diaphragm dividing theeasing into a fuel chamber and a motor chamber, a tension spring in thefuel chamber and associated With the diaphragm for flexing it todischarge fuel from said chamber, and means in the motor chamber forflexing the diaphragm to draw fuel into the fuel chamber and tore-tension said spring, said means becoming effective when the diaphragmreaches its limit of fuel discharging flexure.

HENRY HUEBER. ERWIN C. HORTON.

CERTIFICATE or CORRECTION.

Patent No. 1,926,005. September 5, 1933.

HENRY HUEBER, ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 4,line 67, claim '2, for "fixed" read "flexed"; and that the said LettersPatent should be read with this correction therein that the same mayconform to the record of the case in the Patent Office. i

Signed and sealed this 24th day of Gctober, A. D. 1933,

- F." M. Hopkins (Seal) Acting Commissioner of Patents.

